In the snack food industry, it has been the general practice to dedicate equipment to the production of one, sometimes two, snack food products. For example, cookers are optimized for the production of potato chips and produce that product in great quantities and at rapid rates. Cookers also have been optimized for the production of tortilla chips and produce that product, as well as perhaps corn chips, in great quantities and to a high quality.
Similarly, for the production of pellet based snack food and extruded products, cookers have been optimized to cook those products in their relatively short cooking time requirements as compared to potato chip products. Such products include fried corn curls, pork skins, and other snack food products popped from pellets dropped into hot oil for a brief cooking period.
It is recognized that the aforementioned products have widely different time-temperature cooking profiles. The cooking of all of these products, however, is achieved in a bath of hot cooking oil in which the product is urged along by mechanical as well as oil flow means until reaching a point where the product is withdrawn from the oil and transferred to salting or seasoning equipment, as well as to a product cooler and later conveyed to a weighing and packaging station.
Potato chips are ordinarily cooked in hot oil at 325.degree. to about 390.degree. F. for a period of about 2 minutes 15 to 20 seconds. Tortilla chips are cooked at about 345.degree. to 375.degree. F. for about 45 to 60 seconds. Corn chips are cooked in hot oil at about 355.degree. to 420.degree. F. Pellet derived snack food products including pork skins are cooked in hot oil at about 390.degree. to 400.degree. F. for about 4 to 60 seconds with pork skins being in the 50 to 60 seconds cooking range.
In certain geographical markets for snack foods, it has been found unnecessary that there be produced on a regular basis vast quantities of an individual snack food product say, for example, potato chips. It is more desirable in these markets to produce relatively smaller quantities of many different snack food products so that a producer may cover a broader spectrum of the desired snack foods for the producer's distribution area. Because of the high capital cost, it is recognized that it is oftentimes economically impractical to dedicate several different pieces of equipment to different snack food products.
It has also been found that in certain areas of the world that it is desirable to be able to physically move snack food production equipment from one city to another or to another country so as to accommodate the different product demands as certain products become accepted and larger production equipment is needed. A readily convertible, easily transportable system for producing a wide variety of snack foods is a long sought after and much needed development. In the past, converting a cooker to accommodate a different product was quite cumbersome and generally involved downtime of the cooker on the order of a full work shift to convert from one product to another. Furthermore, certain snack food production equipment was cumbersome to transport readily from one locale to another to serve a different geographic market. If the equipment were able to be configured into modules sized for transport a very desirable economic objective would be realized.
The applicants, Clark K. Benson and Andrew A. Caridis, are among the named inventors on four U.S. patents which have been assigned to Heat and Control, Inc., South San Francisco, Calif. These are U.S. Pat. No. 4,738,193, granted Apr. 19, 1988; U.S. Pat. No. 4,942,808, granted Jul. 24, 1990; U.S. Pat. No. 5,137,740, granted Aug. 11, 1992; and U.S. Pat. No. 5,167,979, granted Dec. 1, 1992. These patents disclose cooking processes and apparatus flexibly adapted to cooking with a time-temperature profile conforming to either a linear or non-linear curve. Several different cooking zones are disclosed in U.S. Pat. No. 5,137,740, and product propulsion means including paddlewheels and submerger conveyors are disclosed in that patent whereas the equipment itself is generally physically large and dedicated for use in a single product production line.